RESUMO
BACKGROUND: This study aims to evaluate the use of the leukocyte- and platelet-rich fibrin (L-PRF) membranes in increasing the width of the keratinized mucosa (KM) around implants. MATERIAL AND METHODS: Eight patients in need for bilateral widening of the KM around implants in the lower jaw were recruited for a spit-mouth randomized controlled trial. At the control site, a free gingival graft (FGG) was used, whereas at the other side (test), L-PRF membranes were applied. The primary outcome was the increase in width of KM around the implants. As secondary outcomes, the postoperative pain and surgical time were assessed. The follow-up period was 6 weeks. RESULTS: A significant increase in the total bucco-lingual width of KM in both groups was observed, with 1.3 mm ± 0.9 extra gain (P < .05) for the FGG sites. Shrinkage of the widened areas in this period was 32.1% at the test site and 23.6% at the control site. All values of the postoperative pain scores at the control site were higher than at the test site. The mean surgery time in the test and control group was 29.1 ± 4.8 and 48.1 ± 7.7 minutes, respectively. CONCLUSION: Within the limitations of this randomized controlled trial with split mouth design, it can be concluded that L-PRF can increase the width of KM around implants. Furthermore, the use of L-PRF results in a lower surgical time with less postoperative discomfort and pain for the patients in comparison to the FGG.